Caster



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ygroove is'ormed in the lower surface of whereby the object o'fi the present invention may be eifectuated that disclosed in the accompanying drawings may be employed and in which z` Fig. 1 is a \`iertical cross section` taken in a. plane transversely of the anis ot vthe wheel hub and through the pivotal airis of the swivel member or the caster, this section beingv taken on the line @-7) of lili 2;

Fig. Qpis a verticaly cross section on line c d of Fig. 1; and

Fig. 8 is a 'fragmentary bottom plan view ol" a portion ci: the supportiugmein or base, illustrating; vthe mode ot preventing; the ball-race ring,v trom rotating.

'lhe base or supporting,` member is indicated at 1, this member preferably being); of substantially circular .torni altliough the exact shape ot this part .is noiressential. This support or base may be provided with holes or slots for the reception oit attaching' bolts whereby the caster may be secured to the truck or rack to which it .is desired to attach the' same. Projectingv downwardly from the center or' the supporting member 1 is a stud 2 havinga radial Vflange 3 constituting a head therefor. llhis stud is iixedly-secured inthe support 1 and may be integral therewith `if desired, it being prelei-red, however, to lform this stud et relatively hard material and to cast it into the base member 1 when the' latter is The head 3 or' the stud 2 is provided with a substantially lat upper race indicated at L1, such Jface being,- spaced from the vadjacent surface of the base member 1. An annular member 1 concentric with the stud 2, 'this groove being indicatedl at l and being delined by the central boss and the annular flange 6. Nithin this groove is seated a ball-race ring .7 which is preferably formed of lsheet material, such for example 'as steel which may be hardened by heat treatment to provide the desired wearing qualities. This ring is` provided with one or more radially extending lugs 8, such lugs within slots formed `inthe tlange 6, as indicated in Fig. Such lugs, when seated in the slots, serve to prevent rotation of the ring; T relatively to the member 1.

Cooperating vwith the base member 1 is a swivel device comprising the coniplen'iental members 9, 10. '.llhese members are of:A substantially send-circular lorm and are provided at their meeting edges with semi-circular notches 'for engagement about the stud `i2. rlllie lower suri'aces oi the members "liange '1e which overlaps theirlange 6' and thus serves to protect the joint between the hase member 1 and the swivel device. 1Within the groove 13 there is seatedv a ball-race ring; 15 which is substantially identical in form with the ring 7, and may be provided .vith one or more radial lugs suoli as S `seated within corresponding yslots in the 'Harige 141. rlhe rings 7 and 15, as herein ot the respective brackets 18, 19 are outstanding;l ribs 211, 25.'

Through the respective brackets and their ribs are formed aligned openings 26, 27 within which is mounted a shaft 2S. .Transverse slots 29, 30 are formed in the rib members 2&1-, 25 such'l slots aligning with trans "verse openings in the ends of the shalt 28.

Cotter pins 31, 32 are passed through such slots and through the openings in the shaft,v

and serve to prevent withdrawal of the shaft from the brackets as well as preventing rotation of the shaft therein, such cotter pins serving; as additional means 'for holding the bracket members together. l

y Mounted to turn freely upon thesha'ft 28 is the hub 33 of a truck wheel The ends ci' thc wheel hub extend substantially into engagement with the inner faces of the bracket members 18, 19, respectively, and

extending outwardlyl from such bracket members are annular flanges 85, 36, respectively, formingN cup-like cavities within which the ends of the wheel hub are seated. rlhe -flanges 35, 36, as thus arranged, serve to cover andprotect the joint between the ends of the wheel hub` and the adjacent 'faces 0'1" the brackets, and thus prevent the accumulation of threads or other foreign material in such joint and which might interfere with the free rotation of the wheel. Pry formino: the members 9, l0 as separate elements the operation of casting,I is Jfacilivtatcd and cheapened, while the same time the employment of av iiXed stud 2 is permitted. Such a stud is particularly'advantageous in that there isno possibility oit the parts becoming loose in use, as frequently happens when the pivot'stud is re tained by a nut or other removable securing; means. y Y such stud integrally with the base member or casting it into the same, there is no dan ger ot its liecoming loose and out'oii proper At kthe same time, `by 'forming alignment when subjected to wear and hard usage. Theuse of the sheet metal race ringsy permits of the removal of the bearing surfaces when worn without necessitating the replacement of the entire casting. f The provision of means for retaining the race rings against rotation is very desirable, as they might otherwise move relatively to the surfaces of the base member and swivel device to such an extent as to produce grooves therein having a tendency to throw the parts out of proper alignment.

Having thus described the invention in a preferred embodiment ot the-same, what I claim and desire to secure by Letters Patent ot the United States is: y

l.. A caster haviufT va base provided with attaching elements, a stud projecting :from the under side ot said base, said stud being immovably iixed in the base and having` an integral head s iaced `from the lower side ot the base, a swivel member comprising a pair ot' complemental parts oi' substantially semi-circularform, each part having a co-ncentric semi-circular recess in its straight edge, said recesses cooperating to form a circular opening for the reception of the stud, anti-friction bearings interposed between the under side of' the base and the upper rtace of the swivel member, parallel bracket members carried by the respective swivel members, a shaft mounted in bearings in the respective bracket members, a wheel carried by the shaft and removable means normally acting to hold said brackets in operative parallel relationship.v

2. A caster comprising a supporting member and a swivel member, means for pivot ally connecting' said members, independent ball-race rings interposed between said members, ball-bearings between said rings, and means for preventing relative movement be-` tween tlie ball-race rings and the respective rwith their openin krality of radial recesses, a. ball-race ring oi said grooves having a radial recess in its outer wall, a ball-racering of sheet-material loosely seated-ineach o' said grooves, said rings each having an integral radial ear en- Y vgaging the respective recesses, and bearings interposed between said rings.

6. A caster comprising a supportinginember and a swivel member, means tor swivelly connecting saidmembers, andan anti-triction device interposed between said members, said device comprising a pair of rings provided respectively with annulargrooves,l

the grooves oi the two rings being opposed to each other whereby to :form an annular channel,` and a series oct balls within-the annular .channel ltormed by the opposed grooves. l

7. A caster comprising a wheel having a hub, a pair of spaced bracket menibershav ing aligned openings, a shaft/ mounted in said openings and supporting said wheel, and a cup-like socket integral with each ot said brackets and serving for the reception ot an end-ot the wheel hub.

8. A caster comprising a pair of independent members provided with openings, means for securing said vmembers together gs 1in alignment, a ishatt having .its vopposite ends mounted in the respective opei'iings, al wheel mounted to turn upon said. shaft, said'wheel having a hub, and lan annular lliange. Aintegral with cach 'of said brackets and concentric with the shaft, the respective iianges overlapping the end portions oi the wheelhub.

9. A .caster comprising a pair of rspaced brackets, said brackets having aligned openings and slots extending transversely oi the respective openings, a shaft mounted within said openings said shaft having transverse holes adjacent its ends, and members passing through said holes and lying within the respective slots'whereby to maintain said shaft in lined position. a

Signed by me at Boston, lvlassacliusetts,

this ilSt-li day oi June, 192i..

JULI US B. Mlll/IZ. 

